[Bridge] [PATCH net-next 2/4] net: neighbor: add fdb extended attribute

[Nikolay Aleksandrov]

Add an attribute to NDA which will contain all future fdb-specific
attributes in order to avoid polluting the NDA namespace with e.g.
bridge or vxlan specific attributes. The attribute is called
NDA_FDB_EXT_ATTRS and the structure would look like:
 [NDA_FDB_EXT_ATTRS] = {
    [NFEA_xxx]
 }

Signed-off-by: Nikolay Aleksandrov <nikolay at cumulusnetworks.com>
---
 include/uapi/linux/neighbour.h | 12 ++++++++++++
 net/core/neighbour.c           |  1 +
 2 files changed, 13 insertions(+)

diff --git a/include/uapi/linux/neighbour.h b/include/uapi/linux/neighbour.h
index eefcda8ca44e..540ff48402a1 100644
--- a/include/uapi/linux/neighbour.h
+++ b/include/uapi/linux/neighbour.h
@@ -30,6 +30,7 @@ enum {
 	NDA_SRC_VNI,
 	NDA_PROTOCOL,  /* Originator of entry */
 	NDA_NH_ID,
+	NDA_FDB_EXT_ATTRS,
 	__NDA_MAX
 };
 
@@ -172,4 +173,15 @@ enum {
 };
 #define NDTA_MAX (__NDTA_MAX - 1)
 
+/* embedded into NDA_FDB_EXT_ATTRS:
+ * [NDA_FDB_EXT_ATTRS] = {
+ *     ...
+ * }
+ */
+enum {
+	NFEA_UNSPEC,
+	__NFEA_MAX
+};
+#define NFEA_MAX (__NFEA_MAX - 1)
+
 #endif
diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index ef6b5a8f629c..8e39e28b0a8d 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -1783,6 +1783,7 @@ const struct nla_policy nda_policy[NDA_MAX+1] = {
 	[NDA_MASTER]		= { .type = NLA_U32 },
 	[NDA_PROTOCOL]		= { .type = NLA_U8 },
 	[NDA_NH_ID]		= { .type = NLA_U32 },
+	[NDA_FDB_EXT_ATTRS]	= { .type = NLA_NESTED },
 };
 
 static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh,
-- 
2.25.4